Questions Young People Ask On Career Choice: Please Give Your Own Advice

In a youth symposium I attended about two weeks ago, some questions were asked by young people which I decided to publish on this site because of those having such questions in mind and for you to give your own opinion, advice or suggestions based on the questions.
Alright, the questions are as follows:

* In a situation whereby your parents want you to study a course but you have no interest in such course, what can you do?

*Building one’s career, is it necessary to be in line with what you studied in school because most parents want their children to practise what was studied in school?

*What can someone do to know the right career to choose in the nearest future?

* How can one discover himself even having the thought of being lost.

This questions are based on careers and academics.
Moreover, I will like hear your responses to these questions. Please feel free to share your own views and opinions concerning these questions.